[Histopathologic and immunohistochemic changes in Helicobacter pylori colonised gastric mucosa]

Helicobacter pylori (H. pylori) colonize gastric mucosa causing both inflammatory changes, premalignant lesions and malignant tumors, including gastric lymphoma and carcinoma. In this study, our propose was to evaluate the histopathological changes corellated with immunohistochemical results demonstrating the types of cellular infiltration and proliferative activity of gastric mucosa infected with H. pylori.

Gastric endoscopic examinations was performed in 468 patients with anti-H. pylori antibodies and dispeptic phenomena. Snippets harvested endobiopsic stomach were fixed in formalin and processed by paraffine inclusion. Histological sections were stained with hematoxylin-eosine and Giemsa. In 65 cases of endobiopsic fragments (36 deep chronic gastritis with intestinal metaplasia, glandular atrophy and intraepithelial neoplasia and 29 carcinomas) immunohistochemical reactions were performed by applying reagents for evidence of H. pylori colonies, of T lymphocytes (CD3) and macrophages (CD68) and Ki-67 reagent for proliferating nuclear antigen labelling.

Endobiopsic specimen found in all H. pylori or by Giemsa staining or by anti-H. pylori antibodies when they were in small numbers. Histologically, were diagnosed : 463 superficial and deep chronic gastritis associated with premalignant lesions, 29 carcinomas, 2 non-Hodgkin's lymphoma and an adematous polyp. Immunohistochemically, inflammatory infiltrate consisted of numerous T lymphocytes, macrophages and lymphoid follicles. Foveolar cell nuclei, in areas of intraepithelial neoplasia and carcinomatous cells were intensely stained with Ki-67, demonstrating increased proliferation.

In gastric infection with H. pylori, inflammatory infiltrat is composed of abundant macrophages and T lymphocytes. Ki-67 was absent or minimal in chronic gastritis, while in areas of intraepithelial neoplasia was positive in both foveolar and coating epithelium. Anti-H. pylori antibodies in human serum remains one of the simplest methods to detect H. pylori, therefore it plays an important role in practice. Medical eradication of bacteria may cancel inflammatory changes, metaplasia and proliferation of gastric mucosa and thus it prevents the cascade of carcinogenesis.